Rule 11.1: Exclude null pointer constant

Null pointer constants can be cast to a function pointer.

Author: lcartey

c/misra/test/rules/RULE-11-1/ConversionBetweenFunctionPointerAndOtherType.expected

@@ -1,7 +1,6 @@
 | test.c:11:8:11:16 | (fp1 *)... | Cast performed between a function pointer and another type. |
 | test.c:11:8:11:16 | (fp1)... | Cast performed between a function pointer and another type. |
 | test.c:12:14:12:23 | (void *)... | Cast performed between a function pointer and another type. |
-| test.c:14:8:14:15 | (fp2)... | Cast performed between a function pointer and another type. |
 | test.c:15:8:15:15 | (fp2)... | Cast performed between a function pointer and another type. |
 | test.c:22:12:22:13 | (fp1)... | Cast performed between a function pointer and another type. |
 | test.c:25:8:25:9 | (fp1)... | Cast performed between a function pointer and another type. |

c/misra/test/rules/RULE-11-1/test.c

@@ -11,7 +11,7 @@ void f1(void) {
   v1 = (fp1 *)v2;        // NON_COMPLIANT
   void *v3 = (void *)v1; // NON_COMPLIANT
 
-  v2 = (fp2 *)0; // NON_COMPLIANT
+  v2 = (fp2 *)0; // COMPLIANT - null pointer constant
   v2 = (fp2 *)1; // NON_COMPLIANT
 
   pfp2 v4;